The effect of contingent imitation intervention on children with autism spectrum disorder and co-occurring intellectual disabilities

Background: Imitation plays a crucial role in the development of social communication, and it is a skill that is often missing in children with autism spectrum disorder and co-occurring intellectual disabilities. Contingent imitation (CI) results in increased social eye gaze, an imitation cue for children with ASD. A series of studies on Reciprocal Imitation Training (RIT) intervention that included CI has demonstrated an increase in imitation frequency. However, little is known about CI intervention's effects on motor, object, and vocal imitation accuracy in children with ASD-ID. Method: The participants in this study were six 4-year-old children with ASD-ID. A single case experimental design with multiple probes across target behaviors was used to identify CI intervention's efficacy on the motor, object, and vocal imitation. Moreover, pre-and post-assessment analysis evaluated socially engaged imitation and imitation turn-taking. Results: Most motor, object, and vocal imitation accuracy increased through the CI intervention. However, individual adaptations such as prompting for looking behaviors and motor responses were required to increase specific target behaviors. Moreover, all children increased socially engaged imitation and imitation turn-taking through CI intervention and CI + prompting intervention. Conclusions: CI intervention is an efficacious intervention method for increasing the accuracy of imitation in children with ASD-ID. Furthermore, CI + prompting intervention is effective when CI intervention alone does not improve imitation accuracy. CI + prompting interventions using a decision tree tailored for each child could identify the intervention strategies for improving imitation accuracy during play activities and increase the understanding of ASD-ID children's imitation accuracy difficulties.